The objective of this research is to apply new techniques of digital image processing to the analysis of red blood cells. It has been demonstrated that these techniques enable very precise and rapid measurements of individual red cells with regard to their hemoglobin content, size, shape and central pallor. Further, subpopulations of cells can be rigorously defined according to characteristic variations of these measurements. These techniques have provided a new investigative tool for clinical medicine, resulting in enhanced, more efficient, anemia diagnosis. One of the primary objectives of this research will be to quantify this improvement in diagnostic capability with clinical studies. These studies will be performed in two parts: 1) Cases of confirmed and known anemias by pre-defined standard techniques will be compared to the confirmed diagnosis. Anemias to be tested in this manner will include iron deficiency, chronic disease, beta thalassemia, megaloblastic, sickle cell, SC trait, and spherocytic. 2) The usefulness of the proposed red cell analysis procedures in actual practice will be tested by comparing populations of anemic patients during the diagnostic process. It is anticipated that the usefulness of the new parameters will result in a decrease in the number of excess tests ordered will be used as a figure of merit to assess the new techniques. Additional methods for quantitative morphological description and classification of red cells will be pursued as necessary, and as indicated by the results of the ongoing clinical studies. Additionally, the relationship between cell thickness, area, volume and cell hemoglobin concentration will be studied using a thin sectioning technique. These results will be used to interpret and standardize image processing thickness/density profiles.